Ensuring Business Continuance via High Availability SANs Page 2

The Interoperability Challenge

Designing a complete SAN-based solution is an extremely complex task which requires research, testing, resolution and documentation in vast detail. To ensure interoperability, each component's various software, firmware, and hardware revision levels must be tested. Furthermore, the complete solution must be examined in order to ensure inclusive compatibility with the intended applications, and detailed processes and methodologies must be developed and documented in order to provide predictable and repeatable results.

There is also the considerable risk of lengthening the return on investment period and perhaps even rendering the project fiscally unfeasible by randomly integrating new technologies within the data center. As a result, a task as complex as architecting a SAN is rarely attempted solely by IT staff, and if it is attempted, it is only for traditional core mission-critical applications. Consequently, many advantageous applications of new technologies are usually not explored until a clear implementation plan has been adopted.

Problems

Distributed data protection is unreliable, difficult to administer, and expensive. To manage the backup, each server requires dedicated tape hardware and personnel. So, while accountable for the protection of all enterprise data, central IT management is entirely dependent on distributed personnel for ensuring backup execution. Compounded by the accumulation of individual backup sites is the complexity and expense of reliably performing best practices, such as judiciously maintaining off-site copies of backups for disaster recovery.

Furthermore, while the centralization of backups by transporting data over the existing LAN to data center tape libraries was an option in the past, today this approach offers limited scalability, preventing it from being able to support the rapid growth in storage that is outpacing the capacity expansion of the LAN. Additionally, backup traffic critically impacts the performance of other key applications, and the LAN is unable to provide a stable platform for mission-critical protection of data traffic. This is due to the diverse number of attached devices. Finally, security may be compromised by routing backup traffic over the LAN.